Hey there!

To be honest only you know studying in which duration help you.

Are you comfortable studying during day or night?

But still I would suggest you do something and you can follow this routine .

Divide your 24 hours into 3 phases.

10 hours + 8 hours + 6 hours

Now ,

10 hours - Only studies (Solving JEE MCQs ,Making notes , writing important stuff, watching videos for JEE etc.)

8 hours - Sleep like a child.

6 hours- Eating, Bathing, Reading Novels, Asking question on career360, Entertainment,Social Media etc.)

I can guarantee you if you follow this religiously you will definitely see a change in yourself.You can increase or decrease time slots according to your convenience like if you think 7 hours of sleep is enough for you ,so make it like

11 hours+ 7hours+6 hours(Your studies has to be your first preference)

Bonus tips

i.Solve Previous Years Question Papers

ii.Try to eat healthy and avoid junk.

iii.Sleep at least for 6 hours.

iv.Test series is a must.

Feel free to ask if you have any more queries.

All the best!